The present invention relates to paper sheet accumulators, and more particularly to a paper sheet accumulator wherein paper sheets are accumulated individually and then dispensed collectively as a stack.
Various accumulators have been used for accumulating paper sheets and documents into stacks and then transporting the accumulated stacks. For example, Driscoll, et. al (U.S. Pat. No. 5,147,092) disclose a flat accumulator comprised of upper and lower sets of driven elastic belts.
While a flat type of accumulator is appropriate for some applications, its dimensions are too large or bulky for other applications. This related art cannot conform to space limitations and layout of certain machines in which a sheet accumulator must form a component part.
In addition to problems of size and shape, the related art also has problems due to the need for paper buckling. For example, Miller, (U.S. Pat. No. 5,356,263) discloses a sheet accumulator in which it is necessary for sheets of paper to buckle very substantially. This becomes problematic, however, when the sheet of paper has characteristics that are not consistent with normal buckling, perforated paper being one example.
The primary objective of this invention is to provide a sheet accumulator for accumulating sheets of paper seriatim (i.e. one by one), and for then allowing the stack of accumulated sheets to exit the device. Another objective of the present invention is to minimize the amount of space required by the accumulating apparatus. Accordingly, the present invention is a compactly designed sheet accumulator in which the paper path is circular. This design conforms to space limitations which other sheet accumulators, such as flat accumulators, are unable to do.
In one embodiment of the present invention, individual sheets of paper moving along a main (linear) path enter into the accumulator one at a time, whereupon each sheet is diverted onto and around a set of rotating, driven disks. The disks are parallel to each other and perpendicular to the paper sheets. Before each sheet of paper completes a full circle, the disks urge each sheet against a set of stops, and each subsequent sheet enters the circular path between the disks and the previous sheet, so that it too is urged and registered against the stops. When the accumulation is complete, the stops are retracted and a set of rollers is engaged to exit the stack of sheets out. The accumulation of sheets then reenters the main (linear) paper path.
The present invention is designed to offer a sheet accumulator with a new compact configuration that allows the accumulator to fit into spaces where other sheet accumulators cannot fit. The present invention is also designed in such a way as to easily handle paper prone to buckling, such as perforated paper.